Battle Mode - Single Battles

Note that in Battle Mode, the opposing Trainer's Pokémon's levels are equal to the challenger's highest level in the team. If the highest level in the challenger's team is less than or equal to 50, the opposing Pokémon's levels are all 50. Also note that in Single Battles, it is 3 versus 3.

Battle Mode - Double Battles

Note that in Battle Mode, the opposing Trainer's Pokémon's levels are equal to the challenger's highest level in the team. If the highest level in the challenger's team is less than or equal to 50, the opposing Pokémon's levels are all 50. Also note that in Double Battles, it is 4 versus 4.